Episode 272: RHS plant trials and AGMs
Tillandsias being trialled for an Award of Garden Merit at Walton Hall. Photograph: Jane Perrone.
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TRANSCRIPT
Music.
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Jane Perrone
Hello and welcome to On The Ledge Podcast. I'm Jane Perrone and this week it's all about the AGM.
Music.
Jane Perrone
We're not holding an annual general meeting, I'm talking about planty AGMs. A way of finding out which plants are really worth growing. And I answer a question about VPD, what it means and how it could affect your houseplants. Do houseplants and birds of prey mix? Well, I discovered the answer unexpectedly last night when a bird of prey flew into my conservatory plant room through an open door. Fortunately, it was a small bird of prey. I think it was a peregrine falcon. And I know you're going to be saying, Jane, pictures or it didn't happen. Well unfortunately I was so focused on the well-being of the bird and not gonna lie, my plants, that my first concern was getting it out the door as quickly as possible, which I did manage to do. It managed to fly behind a set of glass shelves and wedge itself between the shelves and the door, the door that doesn't normally get opened. And I was faffing about getting a oven cloth to think about trying to capture it when my husband wisely said, why don't you just open the other door? Which I did and the bird gratefully flew away. But it was an unexpected drama I have to say and I really wish I had taken some pictures because it was an absolutely beautiful thing and amazingly it didn't do any harm to my plants that I'd seen but it's not something I'd recommend reproducing if you can avoid it.
Jane Perrone
Now I think most of you have probably heard of the RHS, the Royal Horticultural Society. It's a long standing charity here in the UK which supports all things horticultural and probably the RHS is most famous around the world for its shows like RHS Chelsea Flower Show, but it does loads of other work as well. And one of the things I've been involved with for the past few months is the RHS plant trials and the resulting AGMs. And that's what I'm going to be discussing in this week's show. We'll be finding out what an AGM is, how a plant gets awarded an AGM and what it means for you as somebody growing plants and buying plants for your collection.
Music.
Jane Perrone
If you've ever seen the initials AGM written after a plant name, or perhaps seen a small trophy symbol next to a plant in a catalogue, then you have come across the Award of Garden Merit. Now, I have to admit, despite working as a garden editor for many years, I didn't know that much about how the Award of Garden Merit is awarded. I knew that there were some plant trials carried out by the RHS, but I didn't know much more than that, how the trials actually worked and so on. That was until earlier this year when I got asked to be involved in the Tillandsia plant trials for the RHS. So yes, plant trials do include indoor plants as well as outdoor plants. Traditionally, the RHS has focused more on outdoor plants, but they are putting that right now and starting lots more trials for AGMs, for genera that we consider to be houseplants, including of course the Tillandsias, the air plants. So I headed off to Walton Hall, which is a garden in Warrington in the northwest of England, a few months ago to meet up with the other members of the Tillandsia plant trial and find out what it's all about.
Jane Perrone
Now, I am not a Tillandsia expert, so you may be wondering why on earth am I on this panel? Well, the group of people that come together to judge the AGMs for Tillandsias does consist of quite a few real Tillandsia experts. But the RHS believes by having some people like me, who are really knowledgeable about houseplants generally, but not specifically about Tillandias, there's a degree of balance. So, you know, maybe if I was on a Hoya plant trial, I would be just saying, oh, give them all AGMs, but of course that wouldn't be the right thing to do. So by having people who are not particular specialists in a type of plant, hopefully there is some balance and the right plants get awarded AGMs. There are dozens of Tillandsia species, cultivars, and hybrids involved in the trial. Where are these plants coming from though? Well, they are all being grown in a glass house at Walton Hall, and the plants have been sourced from Every Picture Tells a Story, which is a well-known Tillandsia and bromeliad nursery here in the UK, known for its incredible displays at the Chelsea Flower Show and other flower shows around the UK. So for each of the plants chosen, there are three specimens being grown, all in the same conditions. And these conditions are designed to emulate the kind of regular growing conditions that we might be experiencing at home, not giving the plant some kind of planty nirvana, their absolute ideal conditions, because that way we wouldn't really be testing how well they would grow in our own homes, which is the point of the AGM. So the plants are being grown in three different ways, but all grouped together. So if you can imagine, and I do advise you to go and look at the show notes where you can actually see a picture of this.
Jane Perrone Each trio of plants of the same type is mounted on a piece of cork and each one is mounted in a different way. So one just attached to the cork, one is planted in a little pocket and the third is attached to a piece of wire, echoing the kind of ways that we'd grow these plants at home and allowing us to see if one particular type of growing suits a particular plant more. So over the next few meetings, every few months, we'll be turning up at Walton Hall as the plant trials panel and checking out the plants and their progress and then voting on which ones we think are doing well enough to be on their way to getting an AGM. But to do that they have to fill certain requirements. What are those requirements and how does a plant actually get awarded an AGM?
Jane Perrone
Well, I had a chance to chat to David Ford on this very subject. David is the vice chair of of the Tender and Ornamental Plant Committee of the RHS, and Chair of the Surrey Group of Plant Heritage, and holder of the National Collection of Chaenomeles, which are the Japanese quinces, an outdoor hardy plant I highly recommend growing if you have a garden. You get some nice spring blossom and some rather delightfully perfumed little fruits, which you can turn into jelly. Anyway, back to plant trials, let's find out a bit more about how they work with David Ford.
Jane Perrone
Can you break down what the RHS plant trials are and what it means for a plant to have an AGM?
David Ford
Of course I can Jane, it really is fascinating because it's a side of work that the RHS does, as part of their charitable endeavour which I think often gets really missed by the public and what these awards really mean and the amount of work that's gone in that's entailed in the trials, that get the awards made. So the trials themselves, they're brought up by the various plant committees and then through the trials office based at Wisley and now in the other gardens as well, we'll gather together all the experts from around the country and a particular genus of plants, plus a few sort of plant journalists like yourself or other people that are interested and then together we'll assess the plants. I mean for some of the plants, say for bedding plants, obviously this is over a year, but for the perennials and for house plants it can be two, three, four or even five years for some of the woody plants.
David Ford And so what we've got is we've got all those people assessing those plants over a period of time to really come out with the best of that genus that we can recommend for the public to grow. So when someone goes to a garden centre and they see that little trophy symbol and an AGM, RHS AGM, it's the ward of garden merit and although quite confusingly we'll use that for house plants as well, but what it really means is that having looked at all the plants that would be available for the public, these are the ones that the experts would really recommend that you try and grow at home.
Jane Perrone And that is a really useful guide for those people starting out to actually think well actually this is a plant that's well the chances are this isn't going to let me down if I follow the basic instructions which we all kind of need when we're starting out and even if we're experienced, in gardening it's still comforting to have that little AGM symbol as you say and so we're here for the Tillandsia trial at Walton Hall today, can you just run through how this particular trial is working in terms of what's involved and what we're looking for when we're looking at these Tillandsia species and hybrids that we're testing out for the AGM?
David Ford
Oh absolutely, so we're sort of guided by five main criteria when we're looking at plants. So the very first criteria is it has to be a good plant for appropriate use. So what we're saying is that this isn't, when we're looking at Tillandsia particularly, most people would be growing those inside as a houseplant. So those plants that may do well outside, that doesn't make them particularly relevant for an AGM. It's plants in normal uses. So for a houseplant, someone that grew it in the house, it's going to grow really well. So that's the first criteria, that it's grown as normal people would, that it's a good plant. We're looking secondly, that it has a good form. So it represents the genus well. In terms of when we're looking at Tillandsias, we're looking at Tillandsias, we want a nice sort of fine leaf form and a nice bulbous plant and maybe some unusual ones, ones that bloom well. So they've got to have a really good form as well. The other criteria we look for is primarily resistance or relative to the genus, so resistance, to pests and diseases. In terms of Tillandsia, I'm not expecting that to be a criteria that's particularly, important. in other plant groups is, if you were looking at things like Monarda, you'd be looking at resistance to Botrytis infection, so the powdery mildew. So that's the third one. The fourth criteria we're really looking for is that they're stable in terms of its form. So again with the Tillandsia, I wouldn't expect many of those to be unstable, but of course there are many plants when we trial them that prove to be unstable. So you start with a variegated plant and you end up with a plain leaf plant, you start with a plant which has really interesting flowers and sometimes you know over a period of years that interest and that uniqueness goes. So it's things that are relatively stable. The other criteria we're looking for, the fifth one, is that they have to be available. So what we're trying to put together with an AGM is a, real guide to someone. So if you wanted to grow a Tillandsia for example, that not only have we trialed them and these are the plants that are going to give you the best bang for your buck, but on top of that you can actually get hold of, them. So with availability we do have to remove AGMs from plants if they no longer can become available. And I think the other thing the public need to know is that if a plant has lost an AGM it it doesn't necessarily mean it's no longer a good plant; it often means it's no longer available, because these awards we're looking for the average gardener so what we're trying to do all the expertise in the country from the RHS and from all the growers and suppliers and enthusiasts we're trying to condense that down into something to a bite-sized chunk that's really useful for a gardener. So if you're looking for a Tillandsia by the end of this trial we're going to be be able to identify four or five hopefully that will all look quite unique and quite different, but we reckon that these are the ones, if you didn't know which one you wanted, go for one of those because they're going to be the ones that perform the best at home.
Jane Perrone
Yes and it's fascinating to actually be seeing these plants growing in situ and looking at how some of them at this stage we're sort of, we're the jury's out, we're not quite sure yet whether they're going to be getting an AGM, but there are some standout stars already I think that we're sort of starting to think yeah actually this might be, depending on what happens in the next few months and years, be an AGM. How long are we running with this trial? Is it three years?
David Ford
We're running three years. Ideally what I would love is that we have a plant that looks good as a juvenile, so it looks good when someone first buys it and three years later it looks even better. That would be the ideal, but we can't rule out those plants that when you get them maybe they don't look as quite as outstanding but by the second or the third year when they've produced their blooms and you've smelt that perfume that we get actually this is still a really good plant it may not look quite at its best when you first get it but in terms of keeping it on your window still at home it's going to give you all that reward that makes it really worthwhile plant to grow.
Jane Perrone And theoretically you could have a plant trial where you just decide none of these plants deserve an AGM. There's no number, there's no amount that you're looking for?
David Ford
Not at all. I mean we're trying to keep the process as fluid as possible so we never set out with a given set of criteria we're looking for. We allow the people on the forum, all those experts, to come together and try and distill the knowledge. So even the characteristics we're looking for when we plan the trial so certainly when we plan this trial we sat down and we decided an approximate set of criteria we thought we would be going to judge on but certainly that's a very fluid idea and when we've got everyone together and everyone's talking about the plants and bringing in their own bit of expertise their own knowledge of growing the plant over years those can sort of change so those criteria can sort of change but ideally when we bring everyone together, what comes out of the AGM is something that we can all agree on are good plants. For some trials there may be quite a few, for others, there'll be, you know, very few. I've not been on a trial yet where we haven't awarded one AGM. I think when we're looking at what plants we're going to trial, we're looking generally at plants where the genus has become a little confused. So either we've had a lot of plants that were given AGMs at some point in the past and are no longer available and a whole load of plants with no AGMs that actually they're the ones that are around we need to look at. Or they're sort of when we've looking at we've never grown them before so they've never been in a trial before. But ideally when we're putting plant to plant, the trial because the RHS has to put a lot of resources behind that. In terms of getting the plants together, getting the forum together, getting someone to actually be a trials officer, so it's quite a commitment in terms of time and money, all those sorts of resources. So we need, as a committee, we're relatively certain that there will be plants that are AGM worthy before we start.
Jane Perrone
And are there any other houseplant genera that you're thinking, gosh we really need to do some plant trials?
David Ford
There are, we have a slight problem with with actually trialling pure houseplants at the moment with the RHS in terms of glasshouse space and where we can do it. So if we can't actually trial the plants, then what we can do is we can have a roundtable discussion. So we award AGMs in the same sort of way, but we don't actually look at the plants, we rely completely on people's knowledge. So we will assemble a forum of people, again, like the Tillandsia forum, we'll have people that are growers, enthusiastic amateurs, national plant heritage, national plant collection holder, if they're available as well, put them all together in a room for a day and then go through the plants one by one and use their previous knowledge. So sometimes we have to do things like that, so certainly I'm not able to tell you what we've got coming up exactly, but certainly we're looking at things like Peperomias and the Haworthias and the Aloes and there's a whole range of plants that we would like to get through. If I had my wish this was 40 or 50, that the RHS have to make me narrow it down!
Jane Perrone
Absolutely, well it's going to be a really fascinating process to follow along and hopefully listeners can follow along with me and at the end we'll find out which Tillandsias are AGM worthy, which is exciting!
David Ford
It is indeed, it's a very worthwhile exercise and it's certainly the thing that makes me most excited is the privilege of seeing all these plants growing together.
Music.
Jane Perrone
Thanks so much to David for sharing that information and I will be keeping you updated with the progress on the Tillandsia trials and I'm also going to be interviewing Don Billington of Every Picture Tells a Story who are supplying the Tillandsias for the trial in an upcoming episode to talk all about Tillandsia care. So we are going to be Tillandsia central for the next few months, but that's great because they're such good plants and it'll be fascinating to hear which ones come out on top in these plant trials. You may remember from episode 262 back in the spring of 2023, I was talking about Monstra Deliciosa and the fact that as a result of my research for my book Legends of the Leaf, I found out that Monstera deliciosa's variegated form was awarded an AGM from the RHS back in 1972 more than 50 years ago, which I found really interesting. I said I was going to try to find out a little bit more about this from the RHS, which I've duly done. And the information that came back from the RHS Lindley Library was as follows: "You're correct that the plant received an Award of Merit on 28 March 1972 and a Certificate of Cultural Commendation in September 1972. These are awards which the main herbaceous committee awarded to plants or to the grower which are presented at the meetings or at shows. The RHS have not carried out a formal trial of Monstra plants for the award of garden merit, therefore there are no reports." So there I was asking if there were plant trials reports to do with this particular plant because when the plant trials are carried out by the RHS and indeed for the Tillandsia trial that I'm involved in.
Jane Perrone
All of the records will be kept by the RHS ad infinitum for anyone who wants to take a look at them in the future. But because this plant was awarded an AGM via a round table assessment, which was a method that David Ford mentioned in his interview, there aren't any particular records about it. So that's a bit of a shame. And perhaps when I'm next at the Houseplant Committee of the RHS, of which I'm a member, I'll make a representation that it's about time that Monsteras had their own plant trials, because gosh, there's so many more on the market these days and it will be really interesting to do an assessment of which ones really work in a regular house environment. Anyway, I wanted to fill you in on that. I'll include those notes in the show notes if you want to take a look. And remember, full transcripts are now available immediately for new episodes, so do go and check those out at the show notes at janeperrone.com.
Jane Perrone
Time for a little housekeeping update. I've got my dustpan and brush and my white vinegar at the ready. If you are on Patreon you will find that there's a new way of listening to my exclusive Patreon podcast which is called An Extra Leaf and that is on Spotify. You can also now listen to the ad-free versions of the show on Spotify if you are a Patreon subscriber. You basically have to link up your Patreon and your Spotify accounts to do it and if you need any help with that as a Patreon subscriber, please let me know. I'll be happy to help. I will be sending a message around with instructions on how to do that. If you're using Spotify already to listen to podcasts, it's a great way of listening to an extra leaf. And if you don't know what all this Patreon malarkey is about, well, let me explain briefly. It's my monthly crowdfunding platform. So if you really like the show and you want more, more, more, and you also want to make sure that On The Ledge keeps coming, then it's a great way of supporting the show with a small monthly payment.
You can be a Ledge End like new Patreon subscribers Jenny and Vivienne. They've unlocked that extra content plus the legendary December mail out. I need to start thinking about that because it comes around very quickly where I send a special card to everyone at the Ledge End and Superfan level. Thank you also to Crawford and Hannah who've upgraded from Crazy Plant Person to Ledge End. What's the difference between those two tiers? Well crazy plant person you just give a dollar or a pound a month and you don't get much back other than, and this is a big thing, a warm fuzzy feeling for supporting the show. Now if this all sounds good, but you're thinking I kind of want to try it out first - well that's okay you can join people like Devi who just started a seven day trial of Patreon and if at the end of seven days you think yeah it was okay but I don't want to stick with this or pay for it then that's absolutely fine you can cancel. I do love a try before you buy. So if you want any information on all of these aspects of Patreon, head on over to the show notes at janeperrone.com to find out more.
Jane Perrone
It's time to talk VPD, and that means it's question of the week time. This one comes from J. A. Clarke, who wants to know the optimum VPD for Nepenthes Alata and indeed Nepenthes. That means the tropical pitcher plants as a genus. So I guess the first question to ask is what the heck is VPD? Don't feel bad if you've never heard of it though because it is a term that's much more widely used in professional horticulture and amongst people who use grow tents, particularly the cannabis community. So unless you're in one of those categories, you may well never have come across this term and that's absolutely fine. So the VPD initials stand for Vapour Pressure Deficit. But what is it? Well, we need to first look at the difference between another term that relates to water and air, and that's relative humidity. So that's one you will have heard of. Relative humidity tells you how much water there is in the air at the temperature the air is at, because warm air can hold a lot more moisture than cold air. So relative humidity is a ratio telling you how much water vapour is in the air compared with the maximum amount that could be held in the air at that specific temperature. So that's relative humidity.
Jane Perrone
VPD on the other hand, well that's telling us basically how hard it is for the plant to transpire. And it does that by telling us the difference between the pressure inside of the leaf and the pressure outside in the air. And it's usually measured in terms of pounds per square inch or millibars, it's an indication of pressure and it's a difference measurement rather than a ratio measurement. And VPD is not related to temperature. Here's another way of putting it, if you're still trying to get your head around this. So VPD is a difference measurement. It's telling you the difference between how much water vapour is currently in the air and how much water vapour the air could hold if it was completely saturated, that got to the point where just no no more water could be held. Obviously the inside of a leaf, that's basically completely saturated more or less compared to the air, which usually isn't completely saturated. So that produces a gradient, which then allows the plants to transpire. That means releasing water into the air from the leaf. So when VPD is high, it means that transpiration is happening too rapidly. The plant is losing water through the stomata, the breathing holds very, very quickly, and the plant could be in danger of drying out. On the other hand, when VPD is very low, that means transpiration is being hindered. ad the plant may not be transpiring quickly enough to allow water to pass through it and those nutrients to be sucked up via the medium of the water and provided for the plant's needs. The ideal VPD range is going to be different for different plants that you might have in your home.
So a fern might have a very different VPD from a cactus for example. If you want a deeper explanation I found an excellent video which is from a company called Argus which I think makes equipment for measuring VPD and humidity, and I will put a link to that in the show notes because it's a really excellent video that explains both VPD and humidity and the differences between them. So if my explanation hasn't cut the mustard, and yeah, it is a bit complicated, then go and check out that video and you will understand the difference really well. I'll link, to an article I found in Inside Grower magazine which explains the difference between VPD and relative humidity. If you want to go into more depth about this, that's a useful place to start.
Jane Perrone
So now we understand VPD, how does it relate to JA's question concerning Nepenthes? Now I wasn't too sure about Nepenthes and their needs so I asked Tom Bennett who's been on the show before. Tom is the carnivorous plant grower behind Tom's Carnivores, that's Tom's Carnivores dot com. Loads of fantastic information there about Nepenthes and what Tom points out is that Nepenthes love very high humidity at night time so that usually results in a low VPD in other words there's not that much difference between the the pressure in the leaf and the pressure in the air they're quite similar and when the when the VPD is low that means the plants breathing holes are going to be open but they're not going to be able to transpire very much because there isn't that much difference between the conditions in the leaf and outside the leaf in the air, and that's usually what draws the water out when transpiration happens. Now Tom notes, Nepenthes are quite different from many of the plants people grow in tents. They like very high humidity, i.e. a low VPD at bedtime. Close to 100% humidity is common, so the charts you'll find online showing ideal VPD aren't really relevant for Nepenthes. For that reason, I've never paid much attention to VPD. I measure temperature and relative humidity and have found this more than sufficient. So what you need to know really for growing Nepenthes is the fact that, as I say, they need really humid air at night time. I would suspect if you're getting Nepenthes care right, you don't need to overly worry about VPD. If they've got nice humid air, they're going to be pretty happy. Particularly Nepenthes which is one of the most popular and widespread tropical picture plants that are grown. It's been picked because it can cope with a wider range of conditions. It's not a great specialist that's going to require extremely intense care. So, that's the best answer I can give you, J.A. Clark. I'm sorry that it's not like a question of saying a number, but again, without knowing your setup or what you're trying to achieve, it's hard to give a very specific answer. But I hope the explanation of VPD and how it works helps somebody. And yeah, do go and watch that video. It's really, really useful.
Jane Perrone Whew! Technical one this week. I hope that's helped somebody, and maybe you can impress your friends with your newfound knowledge of VPD. If you've got a question for On The Ledge, do drop me a line. The best address is OnTheLedgePodcast@gmail.com. Send me lots of information, pictures, where you are, what you're trying to achieve, and I will do my best to help. That is all for this week's show. I do hope that you have a happy and successful time with your plants in the next couple of weeks before the next episode, and that birds of prey and your plants manage to stay well away from each other. I think it's best. But I, will give you extra bonus points if you have a houseplant called Peregrine. I'll see you soon. Bye!
Music.
Jane Perrone The music you heard in this episode was Roll Jordan Roll by The Joy Drops, The Road We Used To Travel When We Were Kids by Komiku, and Whistle by Benjamin Banger. The ad music is Nothing Like Captain Crunch by Broke For Free. All tracks are licensed under Creative comments, visit the show notes for details.
Ever heard of a plant AGM? In this episode I find out what the RHS Award of Garden Merit is all about, and I ask a question about VPD.
This week’s guest
In this episode I speak to David Ford, vice chair of the Tender and Ornamental Plant Committee of the RHS, chair of the Surrey group of Plant Heritage and holder of the National Collection of Chaenomeles.
Chapters
0:01:16 The AGM: An Introduction and Overview
0:03:40 What is the RHS?
0:04:06 Introduction to the Award of Garden Merit (AGM)
0:05:40 RHS Tillandsia plant trial
0:09:20 Interview with David Ford about what’s involved in the RHS plant trials and AGMS
0:20:10 Variegated Monstera deliciosa AGM origins
0:22:40 Housekeeping update: New way to listen to Patreon episodes on Spotify
0:32:29 Music credits for this episode
The RHS Tillandsia trial is displaying the plants on cork in three different ways to test out how they grow best. Photograph: Jane Perrone.
Check out these notes as you listen…
The Royal Horticultural Society (a British charity) awards AGMs - which stands for Award of Garden Merit - to plants that have proved successful for the average grower. You’ll know a plant has an AGM if it has a small trophy symbol or the initials AGM after the name. There’s more information about the plant trials on the RHS website.
You can see a list of all the RHS’s current plant trials here. Many of the trials take place at the RHS flagship garden Wisley in Surrey, but some take place elsewhere.
If you get the chance to visit Wisley, the trials garden is open to the public so you can go and check out the plants currently under examination.
Other current trials include chillies, the genus Aeonium and shorter types of Narcissus. For more information on RHS plant trials you can contact trials@rhs.org.uk.
The Tillandsia trial I am involved in is happening at Walton Hall and Gardens in Warrington in the northwest of England.
Each of the species, hybrids and cultivars we are looking at in the trial are being tested in three ways, as you can see from the picture above, using a piece of cork as a mount: mounted on a piece of wire, stuck to the cork and planted in a small pocket.
The plants for the trials are being supplied by and grown by Every Picture Tells a Story, an air plant and bromeliad nursery based in Ormskirk. We’ll be hearing more from them in an upcoming episode.
All the Tillandsias in the tiral are ones that are widely available for sale in the UK. Photograph: Jane Perrone
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QUESTION OF THE WEEK
JA Clark wanted to know the optimum VPD for Nepenthes alata and the Nepenthes genus overall (aka the tropical pitcher plants).
VPD stands for Vapour Pressure Deficit and relates to water in the air but is slightly different from relative humidity. Let’s first explain relative humidity nor RH. RH is a ratio telling us the ratio of water vapour in the air versus the maximum that could be held in that air at that specific temperature.
VPD tells us the difference between the pressure inside the leaf and the pressure outside. It’s not a ratio like relative humidity, but instead it tells us the difference between how much water vapour is currently in the air as opposed to how much it could hold if completely saturated. This helps growers understand whether plants are likely to be transpiring at the right rate. If you want to go deeper, there’s a good article on the difference between RH and VPD here. And there’s a video here.
The ideal VPD for your houseplants will vary depending on their type. When it comes to Nepenthes, Tom Bennet of Tom’s Carnivores tells me that Nepenthes really like low VPD around nighttime, but unless you are growing very specialist Nepenthes, all you need to worry about is providing how relative humidity. In particular N. alata is a very commonly available Nepenthes considered suitable for a lot of home settings, so I shouldn’t worry about measuring VPD. Tom’s page on caring for Nepenthes is a great place to start if you want to learn more about tropical pitcher plants.
Do we need to worry about VPD if we’re home growers? Probably not. It’s something pro growers, those using grow tents and cannabis growers pay attention to, but if you are not in those categories, the main things you need to worry about are relative humidity, temperature and light.
Want to ask me a question? Email ontheledgepodcast@gmail.com. The more information you can include, the better - pictures of your plant, details of your location and how long you have had the plant are always useful to help solve your issue.
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Contributions from On The Ledge listeners help to pay for all the things that have made the show possible over the last few years: equipment, travel expenses, editing, admin support and transcription.
Want to make a one-off donation? You can do that through my ko-fi.com page, or via Paypal.
Want to make a regular donation? Join the On The Ledge community on Patreon! Whether you can only spare a dollar or a pound, or want to make a bigger commitment, there’s something for you: see all the tiers and sign up for Patreon here. If you want to try before you buy, you can sign up for a seven-day free trial.
The Crazy Plant Person tier just gives you a warm fuzzy feeling of supporting the show you love.
The Ledge End tier gives you access to one extra episode a month, known as An Extra Leaf, as well as ad-free versions of the main podcast and access to occasional patron-only Zoom sessions.
My Superfan tier earns you a personal greeting from me in the mail including a limited edition postcard, as well as ad-free episodes.
If you like the idea of supporting On The Ledge on a regular basis but don't know what Patreon's all about, check out the FAQ here: if you still have questions, leave a comment or email me - ontheledgepodcast@gmail.com. If you're already supporting others via Patreon, just click here to set up your rewards!
If you prefer to support the show in other ways, please do go and rate and review On The Ledge on Apple Podcasts, Stitcher or wherever you listen. It's lovely to read your kind comments, and it really helps new listeners to find the show. You can also tweet or post about the show on social media - use #OnTheLedgePodcast so I’ll pick up on it!
CREDITS
This week's show featured the tracks Roll Jordan Roll by the Joy Drops, The Road We Use To Travel When We Were Kids by Komiku and Whistle by BenJamin Banger (@benjaminbanger on Insta; website benjaminbanger.com). The ad music is Nothing Like Captain Crunch by Broke for Free.